Interrupter switch operating mechanism



Sept. 27, 1960 J. .1. MIKOS INTERRUPTER swI'rcH OPERATING MECHANISM Filed Nov. 24, 1958 10 Sheets-Sheet 1 P 1960 J. J. MIKOS 2,954,450

INTERRUPTER SWITCH OPERATING MECHANISM Filed. Nov. 24, 1958 10 Sheets-Sheet 2 INVENT OR.

[/wzzZaZmiz J. J. MIKOS INTERRUPTER SWITCH OPERATING MECHANISM Filed Nov. 24, 1958 Sept. 27, 1960 2,954,450

10 Sheets-Sheet 3 INVENTOR.

Jo/ziz J/Vikos,

P 27, 1960 J. J. MIKOS 2,954,450

INTEJRRUPTER SWITCH OPERATING MECHANISM Filed Nov. 24, 1958 10 Sheets-Sheet 4 INVENTOR.

Sept. 27, 1960 J. J. MIKOS 2,954,450

INTERRUPTER SWITCH OPERATING MECHANISM Filed Nov. 24, 1958 10 Sheets-Sheet 5 INVENTOR.

BY W W P 1960 J. J. MIKOS 2,954,450

INTERRUPTER SWITCH OPERATING MECHANISM Filed Nov. 24, 1958 10 Sheets-Sheet 6 INVENTQR. Jo/zrz J [Vi/05,

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INTERRUPTER SWITCH OPERATING MECHANISM Filed Nov. 24, 1958 10 Sheets-Sheet '7 Ad lNV ENT OR.

John J M47105 Sept. 27, 1960 J. J. MIKOS 2,954,450

INTERRUPTER SWITCH OPERATING MECHANISM Filed Nov. 24, 1958 10 Sheets-Sheet 8 H i 1:5": I l: 2M l INVENT OR.

P 1960 J. J. MlKOS 2,954,450

INTERRUPTER SWITCH OPERATING MECHANISM P 1960 J. J. MlKOS 2,954,450

INTERRUPTER SWITCH OPERATING MECHANISM Filed Nov. 24. 1958 10 Sheets-Sheet 10 212 ML 4 M13 4" 4 //5 i k; 7 W //9 i 4 Q OPEN/N6 CL05/NG INVENTOR.

Jo/zzz J. M11105 United States Patent INTERRUPTER SWITCH OPERATING MECHANISM John J. Mikos, Highland Park, Ill., amignor to S & C

Electric Company, Chicago, 111., a corporation of Delaware Filed Nov. 24, 1958, Ser. No. 775,759

17 Claims. (Cl. 200-146) This invention relates, generally, to mechanisms for operating interrupter switches and it has particular relation to mechanisms for operating such switches with a snap action in a coordinated sequential manner for closing against load or fault conditions and for opening the circuit under load conditions with these operations being accomplished after taking the control away from the manual operator. This invention is an improvement over the construction shown in copending application Serial No. 748,912, filed July 16, 1958, and application Serial No. 763,383, filed September 25, 1958, and assigned to the assignee of this application.

In copending application Serial No. 748,912 there is disclosed a disconnecting switch construction provided with a load current interrupter. The load current interrupter is intended for efiecting the final opening of the circuit after the switch blade has been moved out of engagement with a cooperating stationary contact. takes place after the switch blade has been moved well beyond the distance where an arc might restrike between the switch blade and the stationary contact whereupon the load current interrupter is operated to open the circuit in such manner that no external arc is drawn. The contacts of the load current interrupter are arranged and constructed to interrupt satisfactorily load curent up to the normal load current carrying capacity of the disconnecting switch. When the switch blade is swung to the closed position, there is the possibility that the circuit may be completed on a fault. In that case current flow will take place substantially in excess of the normal load current flow through the switch. Since the contacts of the load current interrupter are intended to conduct only normal load current and to interrupt the same, severe damage may be incurred to these contacts if the switch blade should be closed under short circuit conditions and the circuit first completed through the contacts of the load current interrupter. In accordance with the construction disclosed in copending application last referred to, provision is made for closing the contacts of the load current interrupter. as the switch blade approaches the switch closed position. Provided that the movement of the switch blade toward the closed position is suificiently slow, the circuit will be completed first between the switch blade and the stationary switch contact and will not be completed at the contacts of the load current interrupter. However, if the switch blade is moved rapidly toward the switch closed position and the movable contact of the load current interrupter is initiated in its movement toward the closed position, the energy imparted thereto by the fast moving switch blade may be suflicient to cause the movable contact to move in advance of the movement of the switch blade such that the circuit will be completed at the contacts of the load current interrupter even though provision is made for delaying the closure thereof.

The construction shown in copending application Serial No. 763,383 overcomes the disadvantages of the construction shown in application Serial No. 748,912 by This Patented Sept. 27, 1960 providing for making certain that the movable contact of the load current interrupter cannot start its movement toward the closed position until after the switch blade has been moved sufficiently far toward the closed or bridging position that the circuit is completed between the switch blade and a switch contact and current starts to flow. Thereafter, the movable contact of the load current interrupter is moved toward its closed position. The operation of the switch blade in application Serial No. 763,383 is under the control of a quick make quick break operating mechanism the details of construction of which are set forth in and constitute the invention of this application. This quick make quick break operating mechanism is arranged to provide not only the desired quick closing and quick opening action but also to provide for positive full closing of the switch contacts, positive forced movement of the switch blade to insure switch blade travel to open the interrupter contacts by operating force applied to actuate the quick make quick break mechanism, and latching of the switch blade to the mechanism in the fully open switch disconnecting position.

Among the objects of this invention are: To provide an operating mechanism for a disconnecting switch that is simple and efficient in operation and can be readily and economically manufactured and installed; to construct the operating mechanism in such manner that the final closing and initial opening movement of the blade or blades of the disconnecting switch is independent of the speed at which the operator may manually effect the switch operation; to effect conjoint movement of the manually operable means and the switch blade or blades during the initial movement of the latter toward closed or bridging position meanwhile storing energy in a spring and then releasing the stored energy to complete the movement of the switch blade or blades to the closed or bridging position independently of the manually operable means accompanied by operation of the load current interrupter or interrupters to the closed position after the circuit has been first established through the switch blade or blades; to effect conjoint movement of the manually operable means and the switch blade or blades to the fully closed or bridging position in the event that the energy stored in the spring is incapable of effecting such operation; to permit relative movement between the manually operable means and the switch blade or blades during the initial operation of the former toward the open position during which time the latter remain in the closed position and energy is stored in a spring until the manually operable means is moved to a predetermined position whereupon the energy stored in the spring is released and the switch blade or blades are operated to the open position accompanied by the operation of the load current interrupter or interrupters which effect the final opening of the circuit; to effect conjoint movement of the manually operable means and the switch blade or blades from the closed or bridging position followed by operation of the load current interrupter or interrupters to open the circuit in the event that the energy stored in the spring is incapable of effecting such operation; to provide for forcing the movement of the switch blade to operate the interrupter to the open position if friction impedes such operation by the spring alone; and to provide for reverse operation of the manually operable means to effect corresponding switch operation without requiring that the manually operable means first be returned to a predetermined starting position.

Other objects of this invention will, in part, be obvious and in part appear hereinafter.

This invention is disclosed in the embodiment thereof shown in the accompanying drawings and it comprises the features of construction, combination of elements and arrangement of parts that will be exemplified in the construction hereinafter set forth and the scope of the application of which will be indicated in the appended claims.

For a more complete understanding of the nature and scope of this invention reference can be had to the following detailed description, taken together with the ac- .companyingdrawings, in which:

Figure 1 is a view, in front elevation of a three phase load interrupter switch installation in which the present invention is embodied;

.Figure 1A is a view, in side elevation of the construction shown in Figure 1, the illustration being at a reduced scale and showing how the three phase load interrupter switch installation can be operated manually from "a remote point;

Figure 2 is a view, inside elevation, showing one-pole of the three phase load interrupter switch installation, shown in Figure 1, certain parts being broken away and others being shown in section in order to illustrate more clearly the details of construction;

Figure 3 is a view, partly in side elevation and principally in vertical section, showing the details of constrution of the load interrupter, the illustration showing the contacts of the load interrupter in the closed position;

Figure 4 is a view, similar toFigure 3, but showing the load interrupter contacts in the openposition;

Figure 5 is 'a view, similar to Figure 2, but showing the switch blade being moved toward the open position with the opening earn engaging the opening trigger of the load current interrupter, no movement of .the movable contact of theload current interrupter having taken place;

Figure 6 is a view, similar to Figure 2, but showing the switch blade in the full open position with .the triggers of the load current interrupter shown in the positions that they occupy when the movable contact .of the load current interrupter is in the open position as shown in Figure 4;

Figure 7 is a view, similar to Figure 2, but showing the switch blade being moved toward the switch closed position to a location where an arc can be struck between it and the stationary switch contact at the voltage at which the switch is intended to operate with the closing cam engaging the closing trigger of the load current interrupter but no movement of the movable contact thereof having taken place from the position shown in Figure 4;

Figure 8 is a top plan view taken generally along the line 8-8 of Figure 7 and showing the relationship between the contact tip on the stationary switch contact and the arcing contact buttons carried by the switch blade at the time that the latter has been moved within striking distance of the stationary switch contact;

Figure 9 is a View, partly in side elevation and partly in section, of a portion of the frame on which the load interrupter disconnecting switches are mounted and of the quick make quick break operating mechanism;

Figure 10 is a sectional view taken generally along the line 10-10 of Figure 1 showing how one of the arms connected to the insulated link which operates each load interrupter disconnecting switch is mounted on the operating shaft;

Figure 11 is a vertical sectional view at an enlarged scale taken generally along the line 11-11 of Figure 9;

Figure 12 is a top plan View of the shaft cam and cam pawlshown in Figure 11;

Figure 13 is a view in end elevation of the drive shaft;

Figure 14 is a view in side elevation of'the drive shaft shownin Figure 13;

.Figure 15 is a vertical sectional view taken generally along the line 15-15 of Figure 9;

Figure 16 is a vertical sectional view taken generally along the line 1616 of Figure 15;

Figure 17 is a vertical elevational view taken generally along the line 1717 of Figure 16;

Figure 18 is a view, similar to Figure 15, except that the quick make quick break operating mechanism has disconnecting switch 14 is used.

been moved in a switch closing direction to the center position where the spring is compressed to the maximum extent;

Figure 19 is a view, similar to Figure 18, except that the quick make quick break operating mechanism has been moved to the position that it occupies when the load interrupter disconnecting switches are in closed or bridging position 'as'shown in Figure 2;

Figure 20 is a view at an enlarged scale of certain parts of the quick make quick break operating mechanism showing the relationship thereof during opening movement and after the mechanism has been moved past the center position by about one pin diameter; and

Figure 21 is a view, similar to Figure 20, showing the relationship of the parts during closing movement thereof and after the mechanism has been moved past the center position by about one pin diameter.

Referringnow particularly to Figure 1 of the drawings, it will be observed that the reference character 10 designates, generally, a frame formed of structural rolled steel sections thatmay include frame uprights 11 and 12. It will be noted that-insulating barriers 13 are positioned between load interrupter disconnecting switches each of which .is indicated, generally, at 14. Three disconnecting switches 14 are employed for a three phase installation. Where single phase operation is required it will .be understood that only a single load interrupter Since the construction of the load interrupter disconnecting switches 14 is identical, a description of one will sufiice for all of them.

The load interrupter disconnecting switches 14 are mounted on upper and lower transverse angle members 15 and .16 which are secured suitably to the frame uprights 11 and 12 at their ends and on'which the barriers 1-3 are supported. It will be understood that other mounting means can be employed if desired. Upper and lower insulators 17 and 18 are provided for each load interrupter disconnecting switch 14 and they are secured by bolts 19 and 20 to the upper and lower transverse angle members 15 and 16 as shown.

At their outer ends the upper and lower insulators 17 and 18 have secured thereto upper and lower line terminals that are indicated, generally, at 21 and 22 respectively. .T he terminal members 21 and 22 are provided with terminal pads 23 and 24 to permit connection of line conductors. The upper line terminal has a contact tongue 25 formed integrally therewith and projecting outwardly therefrom while the lower line terminal 22 has a hinge member 26 formed integrally therewith and projecting outwardly therefrom. The upper and lower line terminals 21 and 22 are arranged to be interconnected by a switch blade that is indicated, generally, at 27 and is pivoted at 28 to the hinge member 26. The switch blade 27 preferably is formed by a pair of switch blade members 29 and 30 that are spaced apart a substantial distance for the principal portion of their length and engage opposite sides of the hinge member 26 at their lower ends. .Each switch blade member near its upper end is bent inwardly as indicated at 31 in Figure l to provide-a contact section 32 at the upper end with these contact sections being arranged to engage opposite sides of the contact tongue 25 which is relatively thin as compared to the width of the hinge member 26. It will be pointed out hereinafter wherein additional arcing contact construction is provided at the upper end of the switch blade 27 for each of the load interrupter disconnecting switches 14 to insure that the circuit is completed between the contact tongue 25 and the switch blade 27 when the latter is moved to the closed position before the circuit is completed through a load current interrupter to be described. 'It will be understood that tie insulators 17 and 13 are mounted on the frame 10 in the manner described and serve to position the upper and -lower line terminals 21 and 22 in insulated spaced relation and that the switch blade 27 is arranged to interconnect them when it is in the closed position as shown in Figures 1 and 2 of the drawings.

It is desirable that an operating mechanism be provided for quickly moving the switch blade 27 from the switch closed position shown in Figures 1 and 2 of the drawings to the open position shown in Figure 6 and for quickly swinging it to the closed position for completing the circuit in order to limit the duration of arcing on opening and closing of the circuit. Also it is desirable that the switch blade 27 be biased into the closed position to resist magnetic forces that would tend to move it from closed position and that the switch blade 27 be held in the open position where the mechanism is locked in the open position. For this purpose a quick make quick break operating mechanism, indicated at 33 in Figure 1, is employed. The details of construction of the quick make quick break operating mechanism 33 are shown more clearly in Figures 9 to 21 of the drawings and the operation thereof will be described in connection therewith hereinafter. For interconnecting the quick make quick break operating mechanism 33 and each switch blade 27 of the three load interrupter disconnecting switches 14 three links 35 of a suitable insulating material are used. At one end each link 35 is pivoted at 36 to the respective blade switch blade 27. At its other end each link 35 is pivoted at 37 to an arm 38. The arms 38 are secured to a horizontally extending shaft '39 which is journaled on the frame in suitable bearings 40 which can be mounted on the uprights 11 and 12. The shaft 39 extends to have operative connection with the quick make quick break operating mechanism 33 which is capable, as pointed out above, of rotating the shaft 39 in one direction to simultaneously open the switch blades 27 and in the opposite direction to close them simultaneously, in each instance at a relatively high speed.

In order to absorb some of the shock incident to closing of the switch blades 27 by the operating mechanism 33, a pair of shock absorbing members 41 are mounted on each line terminal 21 on opposite sides of the respective contact tongue 25 to underlie and be engaged by the inwardly bent portions 31 of the switch blade members 29 and 36. The shock absorbing members 41 can be formed of a phenolic condensation product or hard rubber or the like and secured by any suitable means, such as cement, to the respective line terminal 21. The shock absorbing members 41 can be formed wholly of shock absorbing material or the shock absorbing action can be provided by a layer of such material at the outer end of a boss cast integrally with each line terminal 21 on opposite sides of the contact tongue 25.

When each switch blade 27 is moved to the open position, it is undesirable that any arc be formed between it and its upper line terminal 21. More specifically, it is desired that no arc be formed under these conditions between the contact sections 32 and the contact tongue 25. Accordingly, the upper line terminal 21 is provided with a depending contact plate 43 and an integrally formed socket 44 with respect to which a load current interrupter, shown generally at 45, is detachably secured by a bolt 46 as described in U.S. Patent No. 2,621,272, issued December 9, 1952.

Figures 3 and 4 of the drawings show the details of construction of the load current interrupter 45. There it will be observed that it includes a contact plate 47 which is arranged to overlie the depending contact plate 43 and to be secured thereto by the bolt 46. Threaded into the lower portion of the contact plate 47 is a metallic plug sleeve 48 which is provided at its inner end with a stationary load interrupter contact 49. Since the contact plate 47 is secured to the contact plate 43 which is formed integrally with the upper line terminal 21 and since the plug sleeve 48 is threaded into the contact plate 47, the stationary load interrupter contact 49 is connected directly to the upper line terminal 21.

' in the closed position. The movable contact 50 is carried at one end of a contact rod 51 that is pivoted at 52 at its other end to an operating mechanism which is indicated, generally, at 53. The operating mechanism 53 is contained within a metallic housing 54 and it includes a link 55 to which the contact rod 51 is pivoted at 52. The other end of the link 55 is pivoted at 56 to one end of a link 57 and the other end is pivoted at 58 to the housing 54. Formed integrally with the link 57 is a stop 59 which limits the movement of the operating mechanism 53 in either the closing or opening direction. Pivoted at 60 intermediate the pivots 52 and 56 on the link 55 is an arm 61 the other end of which is fastened to a rock shaft 62 that is journaled on the housing 54 with its ends projecting therethrough to opposite sides. At one end of the rock shaft 62 there is fastened a closing trigger 63 which is shown by full lines in Figures 2 and 6 of the drawings and by broken lines in Figure 3. At the other end of the rock shaft 62 there is an opening trigger 64 which is angularly spaced, as shown in Figure 3, from the closing trigger 63. A toggle spring 65 interconnects the pivots 56 and the rock shaft 62 for the purpose of providing a snap action in the movement of the contact rod 51 and for holding it in either the closed position shown in Figure 3 or the open position shown in Figure 4 of the drawings.

Any are that is formed on separation of the movable load interrupter contact 50 from the stationary load in-- terrupter contact 49 is drawn in a bore 66 that is formed in a stack 67 of fiber washers which are surrounded by an insulating sleeve 68. One end of the insulating sleeve 68 is threaded into the lower portion of the contact plate 47 while the other end is threaded into a tubular extension from the metallic housing 54. Additional insulation is provided between the contact plate 47 and the metallic housing 54 by a tubular porcelain insulator 69. The are is confined within the bore 66 by a trailer 70 that is formed of suitable insulating material and is connected to the contact rod 51 and moves simultaneously with it and With the movable contact 50. Since the only time that current flows through the contact rod 51 is during the circuit opening operation, it is unnecessary to provide an extremely low resistance path to the switch blade 27. Accordingly, the circuit extends from the contact rod 51 through the link 55 to links 57 and 61 and thence to the metallic housing 54. The circuit to the switch blade 27 extends through a bow contact 73 that is carried thereby, as indicated in Figure 2, and which is arranged to engage projections 74 on the metallic housing 54 during the time that the switch blade is moved away from or toward the contact tongue 25 of the upper line terminal 21.

It will be recalled that the arrangement of the load current interrupter 45 is such that the circuit is opened between the contacts 49 and 50 when the switch blade 27 is swung to the open position. In order to accomplish this an opening cam 75, Figure 6, is secured by rivets 76 to the switch blade member 30. The opening cam has a cam surface 77 that faces away from the pivot axis 28 of the switch blade 27 and is arranged to engage the left side of the opening trigger 64, as shown in Figure 5, as the switch blade 27 is swung to the open position. The continued movement of the switch blade 27 in the opening direction brings the bow contact 73 into engagement with metallic housing 54 with the result that, before the contact sections 32 of the switch blade members 29' and 30 disengage the contact tongue 25, a shunt circuit is provided therebetween through the load interrupter 45. After a suihcient gap has been introduced between the switch blade 27 and the contact tongue 25, the open ing cam 75 engages the opening trigger 64. This positively causes the rock shaft 62 to be rotated in a counterclockwise direction as viewed in Figure 3 of the drawings with the result that contact 50 cannot fail to move out of engagement with the stationary contact 49 and the arc is drawn and extinguished within the bore 66. Figure 4 of the drawings shows the relative positions of the movable parts of the load current interrupter 45 when it isin the open position. It will be noted that the opening trigger 64 has been swung in a counterclockwise direction from its position shown in Figure 3 and that a corresponding movement of the closing trigger 63 has taken place.

When the switch blade 27 is in the fully open position it can occupy the position shown in Figure 6. Here the closing trigger 63 is shown in the position that it occupies, as shown in Figure 4, when the load current interrupter 45 is in the open position.

As pointed out in the copending applications above referred to, it is desirable that the circuit not be closed through the load interrupter 45 on initial engagement of the movable contact 5% with the stationary contact 4-9 in the load current interrupter 45 or when the switch blade 27 comes close enough to the contact tongue for an arc to be struck when the switch blade 27 is moved toward the closed position. Accordingly, as disclosed in the aforesaid copending applications, provision is made for delaying the closing of the load current interrupter until the circuit .has been completed between the switch blade 27 and the contact tongue 25 of the upper line terminal 21. For this purpose there is secured by rivets 78, Figure 2, to the switch blade member 29 an arm 79 which extends from the switch blade 27 in the direction of opening movement thereof. At the outer end of the arm '79 there is secured by rivets St) a closing cam 81 which has a cam surface 82 that faces outwardly or away from the pivot axis 28 and is arranged to engage the right hand side of the closing trigger as when the switch blade 27 is swung toward the closed position.

As pointed out hereinbefore, when the switch blade 27 .is moved quickly toward the switch closed position and the cam surface 82 of the closing 81 engages the closing trigger 63, there is the possibility that sufiicient energy .may be imparted into the operating mechanism 53, contact rod 51, movable load interrupter contact 56 and trailer 70 thatwill cause the movable load interrupter contact to move in advance of the movement of the switch blade 27 to such an extent that it will approach the stationary load interrupter contact 49 and complete the circuit before the circuit is completed between the switch blade 27 and the contact tongue 25 on the upper line terminal 21. Under these circumstances the circuit is first completed between the contacts 9 and 5% of the load current interrupter 4-5 and, if the circuit is closed on a fault, substantially more current will flow through the contacts 49 and 50 than they are intended to carry. They become burned and pitted. in addition the heat of the arc incident to such operation may vaporize adjacent portions of the stack of fiber washers 67 and cause the bore 66 to be severely eroded. Then, before a subsequent operation of the load interrupter disconnecting switches 14 takes place, the load current interrupters 45 should be removed and repaired.

In accordance with the construction disclosed in copending application Serial No. 763,838 provision is made for insuring that under no circumstances will the circuit be completed between the contacts 49 and 5t) of the load current interrupter i5 before the circuit is completed directly between the switch blade 27 and the contact tongue 25 on the upper line terminal 21.

As shown more clearly in Figure 5 of the drawings the contact tongue 25 is provided with an upwardly extending contact extension 85 that has an integrally formed arm 86 which extends toward the switch blade 27. On the under side of the arm 86 there is a'cylindricalarcing contact tip =87, formed of suitable arc resisting material, and it is held in place by a stainless steel cap screw 88. For cooperating 'with the cylindrical arcing contact tip 37 a pair of arcing contact buttons 89 are provided as shown more clearly in Figure 8 of the drawings. The arcing contact buttons 89, like the arcing contact tip 87, are formed of arc resisting material and are arranged either to lightly engage opposite sides of the tip 87 or to move in close proximity thereto but not in mechanical engagement therewith when the switch blade 27 is moved to closed position. They are held in place by bolts 90 on the upper ends 91 of the switch blade extensions 92. The switch blade extensions 92 have outstanding foot portions 93 which are secured by rivets 94 to the inwardly bent portions 31 of the switch blade members 29 and 30. The auxiliary contact extension 85, arm 86 and tip 87 not only permit initiating the arc in conventional manner to limit the damage to the contact tongue 25 in closing on a fault but also they provide for more travel of the switch blade 27 to operate the load current interrupter 45 to closed position after the circuit is established by the are.

When the switch blade 27 is in the switch closed position, as shown in Figure 2 of the drawings, the circuit is completed through it between the upper and lower line terminals '21 and 22. When the switch blade 27 is swung toward the open position as indicated by the arrow 95, Figure 5, the bow contact 73 engages one of the projections '74 on the underside of the metallic housing 54 and thereby places the load current interrupter 45 in shunt with the upper line terminal 21 and switch blade 27. The opening movement of the switch blade 27 continues in the direction indicated by the arrow 95 until the cam surface 77 on the opening cam 75 engages the left hand side of the opening trigger 64. At this time the distance indicated at 96 between the arcing contact tip 37 and the nearest part of one or the other of the switch blade extensions 92 is such that, if the circuit were at that time opened by the load current interrupter 45, no arc would be restruck directly between the switch blade 27 and the upper line terminal 21. Thereafter the opening movement of the switch blade 27 is accompanied by a rotation of the rock shaft 62 and the circuit is opened by separation of the movable load interrupter contact 5% from the stationary load interrupter contact 49 within the bore 66 and the arc incident to such operation is there drawn and extinguished. The movement of the switch blade 27, as operated by the quick make quick break operating mechanism 33, continues to the full open position shown in Figure 6 of the drawings. At this time the parts of the load current interrupter 45 are positioned as shown in Figure 4 of the drawings. When the quick make quick break operating mechanism 33 is energized to move the switch blade 27 toward the closed position as indicated by the arrow 97 in Figure 7 of the drawings, the operation continues with the circuit remaining open until, as shown in Figure 8 of the drawings, the arcing contact buttons 89 approach the arcing contact tip 87 to the distance indicated at 98. The distance from the arcing contact tip 87 to one or the other of the arcing contact buttons 39 is such that, at the rated voltage of the load interrupter disconnecting switch M, an arc will be initiated between one or the other of the arcing contact buttons 89 and the contact tip 87. In the event that the circuit is being closed on a fault, the current flow through such an arc will be of corresponding magnitude. Its duration will be relatively short for the reason that the switch blade 27 is moved at a high speed to the fully closed position by the quick make quick break operating mechanism 33.

At the time that the arcing contact buttons 39 are within arcing distance, as indicated at 98, of the arcing contact tip 87, the cam surface 32 on the closing cam 81, Figure 7, first engages the right hand .side of the closing trigger 63. The arrangement is such that no movement of the closing trigger 63 or movement of the movable load interrupter contact 50 is initiated until the switch blade 27 has been swung to such a position that the arcing contact buttons 89 are brought into are striking distance 98 from the arcing contact tip 87. Thereafter, continued movement of the switch blade 27 in the direction indicated by the arrow 97 is accompanied by movement of the closing trigger 63 and corresponding movement of the movable load interrupter contact 50 back to the closed position shown in Figure 3. Since no movement of the movable load interrupter contact 50 is initiated until after the circuit is completed through the arc established between one or the other of the arcing cont-act buttons 89 and the arcing contact tip 87, there is no possibility that the circuit will be completed under fault current conditions or any other conditions between the contacts 49 and 50 of the load current interrupter 45.

As pointed out hereinbefore, the details of construction of the quick make quick break operating mechanism 33 are shown more clearly in Figures 9 to 21 of the drawings. Reference now will be made to these drawings in connection with the preceding figures, particularly Figure 1A.

It will be observed that the manner in which the arms 38 are secured to the operating shaft 39 is shown in Figure 10. Here bolts 38 secure the arm 38 to a clamp 99 on the opposite side of the operating shaft 39 and thereby securely clamp the arm 38 in position. It will be understood that the location of each arm 38 on the operating shaft 39 will depend upon the particular construction employed and the length of the associated insulating link 35. For a given switch installation the arms 38 will be of like construction and positioned in alignment along the operating shaft 39 to rotate conjointly therewith for moving the switch blades 27 into and out of closed or bridging position.

Figure 9 shows the quick make quick break operating mechanism 33 to include a generally C-shaped bracket 100 having inturned ends 101 and 102 that are secured by bolts 103 and 104 to one flange of the frame upright 11. It will be noted that one of the bearings 40 for the operating shaft 39 is mounted on the frame upright 12 and that the other bearing 40 is mounted on the central portion of the O-shaped bracket 100.

Also mounted on the one flange of the frame upright 11 is a third bearing 105 in which is journaled a drive shaft 106 which may be relatively short and which projects for limited distances on opposite sides of the bearing 105. Any suitable means can be employed for rotating the drive shaft 106. For illustrative purposes a sprocket 107 is shown and it is non-rotatably secured to the drive shaft 106 by a transverse pin 107'.

As shown in Figure 1A of the drawing the sprocket 107 on the drive shaft 106 is connected by a chain 108 to a second sprocket 109 that is mounted on an operating as sembly 110 which is carried by a suitable stationary support 111 that is remote from the drive shaft 106. For example, the stationary support 111 can be the front panel of metalcl-ad switch gear or the like. An operating handle 112 is mounted on the operating assembly 110 and is arranged to rotate from the position shown in the drawing through 180 to an alternate position for effecting movement of the switch blades 27 of the load interrupter disconnecting switches 14 from the closed or bridging positions to open circuit position. While the movement of the operating handle 112 and sprocket 109 associated therewith is through 180 in each direction, the movement of the sprocket 107 is somewhat less because of stretch in the chain 108 and the use of different diameters for the sprockets 107 and 109. In addition, because of certain lost motion between the drive shaft 106 and the operating shaft 39, to be described, the operating shaft 39 moves through only 90 between the open and closed position while the drive shaft 106 moves through 121.

As shown more clearly in Figures 9, 13 and 14 of the drawings the drive shaft 106 is provided with a radial extension 115 which has near its outer end a laterally extending arm 116. The arm 116 is parallel to the axis of rotation of the drive shaft 106 which is located along the axis of rotation of the operating shaft 39. The laterally extending arm 116 projects into an arcuate slot 117, Figure 15, of a sector shaped toggle carrier 118 and is arranged to engage either one or the other of arcuately spaced shoulders 119 and 120 that are located at the ends of the arcuate slot 117 as shown in Figure 17. The toggle carrier 118 is rotatably mounted about the axis of rotation of the operating shaft 39 and of the drive shaft 106 and is supported by a roller bearing 121 on a reduced diameter end section 122 of the operating shaft 39. The end section 122 is formed integrally with a shaft insert 122 that is telescoped within and rotates conjointly with the hollow operating shaft 39. Since the toggle carrier 118 has an anti-friction mounting on the operating shaft 39 as provided by the roller bearing 121, the toggle carrier 118 can rotate relatively freely even though a heavy load is applied thereto by a spring to be described.

The toggle carrier 118 is provided with a pair of integrally formed radially extending arms 123, Figure 16, through which a driven pin 124 extends. The drive pin 124 has an extension 124 the purpose of which will be set forth presently. One end of a toggle link .125 is rotatably mounted on the portion of the drive pin 124 that is located between the arms 123. The other end of the toggle link 125 is rotatably mounted by a pin 126 on the underside of a spring carrier 127 that is arranged to move longitudinally in an elongated cylindrical spring carrier guide 128 which is welded or otherwise secured at its lower end to the lower portion of the C-shaped bracket 100. Within the elongated cylindrical spring carrier guide 128 there is a coil compression spring 130. The lower end of the spring 130 bears against the upper side of a retaining washer 131 which, in turn, bears against an upwardly facing flange on the spring carrier 127. The downward movement of the retaining washer 131 in the spring carrier guide 128 is limited by an annular stop 132. The stop 132 also serves to limit the downward movement of the spring carrier 127 through the action of the spring 130. The upper end of the spring 130 bears against the underside of one of a pair of retaining washers 133 the upper of which bears against radial pins 134 that extend inwardly through the upper end of the spring carrier guide 128. Preferably three pins 134 are employed.

It will be understood that the spring 130 is assembled within the spring carrier guide 128 between the retaining washers 131 and 133 under a substantial degree of pretension or preloading. Among the reasons for pretensioning or preloading the spring 130 are:

(1) To keep to a minimum the change in spring loading applied to the spring carrier 127 throughout its full range of movement.

(2) To hold the switch blades 27 in the open position after operation to this position praticularly where the switches 14 are located in a horizontal upright position where the force of gravity biases them toward closed position.

(3) To hold the switch blades 27 in the closed position after operation to this position even though the operating handle 112 is not locked in the fully closed position.

(4) To cause the switch blades 27 and parts movable therewith to move with relatively high velocity while requiring a minimum of movement of the spring 130.

(5) To function as a shock absorber capable of absorbing the kinetic energy of the moving parts at the conclusion of the opening movement of the switch blades 27.

Extending upwardly from and movable with the spring carrier 127 is a tubular spring carrier extension 135. The spring 130 is located around the extension 135. At its upper end the tubular spring carrier extension 135 is provided with a transverse pin 136-which'bears against the upper side of a thrust washer 137. Between the underside of the thrust washer 137 and the upper side of the upper of the two retaining washers 133 are two dampening rings 138 which may be formed of rubber like material and serve to cushion the downwardly movement of the tubular spring carrier extension 135 and parts rigidly movable therewith at the ends of the operating strokes of the quick make quick break operating mechanism 33.

It will be recalled that the extension 124 of the drive pin 124 projects beyond one side of the toggle carrier 118. The extension 124' overlies an arcuate slot 1 511, Figure 11, in a shaft cam 141 which is secured by a transverse pin 142 to the operating shaft 39. The transverse pill 142 also extends through the shaft insert 122. The drive pin extension 124' is arnanged to engage one or the other of arcuately spaced shoulders 143 and 144 at the ends of the arcuate slot 14-0. By this means conjoint rotation of the shaft cam 141 is effected with the toggle carrier 118.

It is desired, when the drive shaft 106 is rotated in a clockwise direction, as viewed in Figure 15 of the drawings, for the purpose of effecting a corresponding rotation of the operating shaft 39 and movement of the switch blades 27 from the fully open position toward the closed or bridging position, that such movement of the switch blades be effected conjointly with the rotation of the drive shaft 106. On the other hand, when the drive shaft 105 is rotated in a counterclockwise direction from the position shown in Figure 19 of the drawings, it is desirable that no movement of the switch blades 27 takes place until after the coil compression spring 130 has been sub stantially fully stressed to its maximum, whereupon the contact sections 32 of the switch blades 26 are forcibly pried loose from the respective contact tongue 25, and the toggle link 125 is moved slightly past the center position as shown in Figure 20. In order to provide for such operations a cam pawl 145 is rotatably mounted by a pin 146 on the shaft cam 141. The cam pawl 145 is biased to the position shown in Figure 11 by a spring 147 which, as shown more clearly in Figure 12, is wrapped around a pin 148 with one end 149 bearing against a pin 15% that is carried by the shaft cam 141 while the other end 151 of the spring 1 17 bears against a tail portion 152 of the earn pawl 14-5 and acts to bias it in a counterclockwise direction as viewed in Figure 11. A shoulder 153 is provided on the other end 154 of the cam pawl 145. It will be observed that the shoulder 153, as viewed in Figure 11, faces the shoulder 143 for the purpose of trapping the drive pin extension 124/ there'oetween under certain operating conditions.

It is desirable that the cam pawl 14-5 be moved out of the path of the drive pin extension 124' when the switch blades 27 are in the closed or bridging position and the parts of the operating mechanism 33 occupy the positions illustrated in Figure 19 of the drawings. The reason for this action is to permit the switch blades 27 to be pried loose from their switch closed positions after the spring 136 has ben compressed to the fullest extent as outlined above. For this purpose a cam surface 155 is provided on the underside of the tail portion 152 of the cam pawl 145. The .cam surface 155 is arranged to be engaged by a detent156, Figure 15, when the shaft cam 141 is rotated to the position shown in Figure 19 of the drawings corresponding to the closed or bridging position of the switch blades 27. The detent'156 is in the form of a rectangular bar that may be secured by welding as indicated at 157 to the inner side of the C-shaped bracket 1130. It will be understood that the spring 131 in the position of the mechanism as shown in Figure 15 of the drawings exerts a substantial downward thrust which is transmitted through the retaining washer 131 to the annular stop 132 at the lower end and is restrained at the upper end by the spring guide 128. This spring force resists any attempt to move the spring carrier 12.7 and parts attached thereto upwardly. Under these conditions the drive pin extension 124 of the drive pin 124 is adjacent the shoulder 143 on the shaft cam 141 and the cam pawl 145 occupies the position shown in Figure 11 of the drawings where the shoulder 153 is on the other side of and is adjacent the drive pin extension 124/, The spring 130 here resists movement in either direction of the switch blades 27 from the open position shown in Figure 6 since they are directly connected to the shaft cam 141 through the shaft 39 and the shaft earn 141 through the cam pawl 14-5 or shoulder 1- 13 reacts through drive pin 124-, toggle link 1125 and spring carrier 127 against the lower end of spring 1311 or through the spring carrier extension 135 against the other end of the spring 130. Also under these assumed conditions of the laterally extending arm 116 from the radial extension of the drive shaft 1116 engages the shoulder 119 on the toggle carrier 118 and prevents further movement of the switch blades 27in the opening direction,

Now when the operating handle 11; is swung upwardly in a clockwise direction, Figure 1A, the sprockets 109 and 167 are correspondingly rotated. Also, the toggle carrier 118 is rotated in a clockwise direction, as viewed in Figures 15 and 21, together with the shaft cam 141 and the operating shaft 39. There is a direct drive to the switch blades 27 and they are rotated toward their closed positions. This operation is accompanied by further compressing the spring 1311 through the toggle link and upward movement of spring carrier extension 135. The compression of the spring 1313 continues until the toggle link 1255 occupies the center position as shown in Figure 18. in this position the longitudinal axis of the toggle link 1125 is coincident with the longitudinal axis of the spring guide 123 which, when projected, extends through the axis of rotation of the drive shaft 1%. When the toggle link 125 is in the center position the switch blades 27 have been operated about half way past the respective interrupter housings 54 and are moving toward the position illustrated in Figure 7 of the drawings where the circuit subsequently can be completed between the contacts 37 and 85 at the voltage for which the switch is designed to operate. A slight movement of the toggle carrier 118 past the center position that is shown in Figure 18 permits the spring 139 to unload and to drive the toggle carrier 11$ toward the position shown in Figure 19 of the drawings. As shown in Figure 21, as the toggle carrier 11? and the shaft cam 141 rotate in the closing direction, indicated by the arrow 158, the drive pin 124 moves a distance about equal to the diameter of the drive pin 124 past a line 159. extending through the center of pin 126 on the spring carrier 137 and the axis of rotation of the drive shaft 1116. This extent of movement past the center position is required to overcome the friction between the moving parts after which the spring 1319 expands to drive the switch blades 27 at high speed through the position thereof shown in Figure 7. By so doing, the arcing time is reduced to a minimum and magnetic forces tending to oppose closure of the switch blades 27 are overcome. The spring 131) drives the shaft earn 141 through the drive pin extension 12 5. This effects a corresponding rotation of the operating shaft 39 and final movement of the switch blades 27 to the closed or bridging position accompanied by operation of the load current interrupters 45 to their closed position. This further operation after the toggle link 125 moves past the center position shown in Figure 18 takes place independently of the movement of the operating handle 112 and is permitted since the laterally extending arm 116, which rotates conjointly with the drive shaft 1%, is positioned in the arcuate slot 117. Relative movement can take place between the arm 116 and the toggle carrier 118 to the extent permitted by the length of the arcuate slot 117.

If for some reason, such as encountering unexpected friction between the contact sections 32 of the switch blades 27 and the contact tongues 25, the spring 130 should be unable to effect the complete movement of the switch blades 27 to the closed or bridging position, then the continued rotation of the operating handle 112 by the operator in the clockwise direction will cause the arm 116 again to engage the shoulder 119 on the toggle carrier 118 with the result that the assembly can be driven manually to the fully closed position. In this manner on completion of the closing movement of the operating handle 112 the operator is certain that the switch blades 27 are fully closed for full current carrying capacity and that the load current interrupters 45 are closed. It is then possible to lock the switch blades 27 in the fully closed position by locking the operating handle 112 in this position. In the switch closed position, the detent 156 engages the cam surface 155 on the underside of the tail portion 152 and holds the cam pawl 145 out of the path of the drive pin extension 124' as shown in Figure 19.

It will be understood that the operating assembly 119, Figure 1A, includes means for locking the operating handle 112 in either extreme positions. Accordingly, the switch blades 27 are thereby locked in the closed or bridging position when the operating handle 112 has been rotated to the position shown in Figure 1A of the drawings. The reason for this is that the arm 116, as shown in Figure 19 of the drawings, engages the shoulder 119 on the toggle carrier 118 and the drive pin extension 124' engages the shoulder 143 on the shaft cam 141.

When the switch blades 27 are to be moved out of their closed or bridging position, the operating handle 112 is unlocked and it is rotated in a counterclockwise direction as viewed in Figure 1A of the drawings. The rotation of the operating handle 112 continues and it is accompanied by rotation of the drive shaft 106 in a counterclockwise direction, as indicated by arrow 160 in Figure 20, together with a corresponding movement of the arm 116 in the arcuate slot 117. The arm 116 engages the shoulder 120 on the toggle carrier 118 and thereupon conjoint rotation thereof in a counterclockwise direction from the position shown in Figure 19 is effected. Through the toggle link 125 the spring 130 is again loaded. However, no movement of the shaft cam 141 takes place immediately nor is the operating shaft 39 rotated or the switch blades 27 moved away from the switch closed or bridging position thereof. The reason for this is that the cam pawl 145 has been depressed, as previously described, and the drive pin extension 124 moves in the arcuate slot 140 toward the shoulder 144 at the other end.

At the time that the drive pin extension 124' engages the shoulder 144 additional torque transmitted through the drive shaft 106 is then transmitted directly to the operating shaft 39 and the switch blades 27 are initiated in their swinging movement to disengage the respective contact tongues 25. As shown in Figure 2 this occurs after the drive pin 124 has moved a distance about equal to its diameter past a line 161 joining the center of pin 126 and the axis of rotation of the drive shaft 106. At this time the contact buttons 89 are still in contact engagement with the contact tips 87 and the bow contact 73 is engaging the first of the projections 74 on the housing 54. The switch blades 27 are rapidly moved by the spring 130 toward the open position and are moving at high speed when they reach the position shown in Figure 5 of the drawings. There is substantial kinetic energy available to accelerate rapidly the movable contacts 50 of the load current interrupters 45 since the switch blades 27 and parts moving therewith are moving at high speed. The switch blades 27 are driven at this high speed by the spring 130 toward the full open position accompanied by operation of the respective load current interrupter 45 which, it will be recalled, effect the final opening of the circuit. One reason for this high speed operation is to reduce to a minimum the time during which current flows through the load current interrupters 45. By separating the contacts 49 and 50 thereof at high speed, arcing time is reduced and the life thereof and of associated parts is increased,

The movement of the switch blades 27 to the open position shown in Figure 6 takes place under the driving force exerted by the energy releasedfrom the spring and as a result of the momentum imparted thereto by the spring 130. During the counterclockwise movement of the shaft cam 141 the tail portion 155 of the cam pawl 145 moves out of engagement with the detent 156 and the shoulder 153 is moved to the position shown in Figure 11. At this time the drive pin 124 is at the other end of the slot 140. Because of the momentum of the switch blades 27 and parts moving therewith, they continue :to move toward the open position after the drive pin 124 stops in the position shown in Figure 15 as a result of the engagement of the retaining washer 131 with the stop 132. The shaft cam 141 continues to rotate to the position shown in Figure 15 and the cam pawl 145 is depressed as this relative movement takes place. Then the cam pawl 145 snaps to the position here shown and traps the drive pin 124 between the shoulder 153 on it and shoulder 143 on the shaft cam 141. When the shoulder 143 engages the drive pin 124, the spring 130 then acts as a shock absorber through the spring carrier extension to the upper end of spring 130 to arrest further opening movement of the switch blades. Movement of the switch blades 27 in a reverse or closing direction is transmitted through the shoulder 153 on the cam pawl 145 to the lower end of the spring 130 which again acts as a shock absorber.

Should friction be encountered or for some other reason the spring 130 be unable to effect the complete movement of the switch blades 27 to the open position, the continued movement of the operating handle 112 toward the lowermost position causes the arm 116 to engage the shoulder 120 on the toggle carrier 118. Since the drive pin extension 124 already is in engagement with the shoulder 144, the operating handle 112 is able to directly drive the switch blades 27 and thereby operate the load current interrupters '45 to interrupt the load current.

When the shaft earn 141 approaches the fully open position, shown in Figure 15 of the drawings, the cam surface is moved out of engagement with the detent 156 and the spring 147 returns the cam pawl 145 to the position shown in Figure 11,. This moves the shoulder 153 on the cam pawl 145 into the path of the drive pin extension 124 and any recoil of the moving parts from the fully open position is applied to the spring 130.

The switch blades 27 are held in the open position, shown in Figure 6, by the spring 130 acting through the drive pin extension 124' and against shoulder 153 on the cam pawl 145 as shown in Figure 15. The shaft cam 141, which is pinned to the operating shaft 39, is thereby held against movement and, since the switch blades 27 are directly connected by the insulated links 35 to the arms 38 which are fast on the operating shaft 39, the switch blades 27 are held open. The locking means associated with the operating assembly 110, Figure 1A, locks the switch blades 27 in the open position.

The lengths of the arcuate slots 117 and 140 are such that, if the operating handle 112 is stopped in an inter mediate position, corresponding to the center position of the toggle link 125 and the spring 130 moves the mechanism past the center position, no shock will be applied to the operating handle 112 tending to move it in one direction or the other.

An important feature of the quick make quick break operating mechanism 33 constructed as described resides in the fact that the operating handle 112 can be reversed after the spring 130 has been operated past the center position without requiring that the operating handle 112 be moved to the end position before such reverse movement is effected. Should the operator decide that 15 he must reverse the immediately preceding switch operation, either closing or opening, he can do so at once without losing the proper sequence of operation of the switch blades 27 and load current interrupters 45 and also without feeling any blow being transmitted through the operating handle 112 to his hands.

While the quick make quick break operating mechanism 33 has been shown and described as being located on the right side of the frame it), it will be understood that appropriate changes can be made therein for positioning it on the left side of the frame It will be understood that the quick make quick break ope-rating mechanism 33 is particularly well adapted to operate the switch blades A47 to close the circuit before the contacts 49 and of the load current interrupters 45 are closed and thereafter close these contacts. However, the quick make quick break operating mechanism 33 also can be used where the arrangement is such that the circuit is first completed by closure of contacts 49 and 50 followed by engagement of the switch blades 27 with the respective contact tongues 25.

Since certain changes can be made in the foregoing construction and different embodiments of the invention can be made without departing from the spirit and scope thereof, it is intended that all matter shown in the ac companying drawings and described hereinbefore shall be interpreted as illustrative and not in a limiting sense.

What is claimed as new is:

l. A mechanism for moving a switch blade into and out of bridging position with a pair of spaced switch contacts comprising, in combination, an operating shaft journaled to rotate about its longitudinal axis and operatively connected to said switch blade to move the same, a shaft cam secured to and rotatable with said operating shaft and having a pair of radially extending arcuately spaced shoulders, a toggle carrier journaled to rotate about the axis of rotation of said operating shaft and having a pair of radially extending arcua-tely spaced shoulders, a drive pin extending laterally from said toggle carrier and spaced from its axis of rotation and overlying said shaft cam to engage one or the other of said arcuately spaced shoulders thereon depending upon the direction of movement of said drive pin, a toggle link pivotally connected at one end to said toggle carrier and pivotally connected to a spring carrier at the other end, a spring guide stationarily mounted in spaced relation to said operating shaft for slidably receiving said spring carrier at one end, a coil compression :spring interposed between the other end of said spring guide and said spring carrier and biasing said toggle carrier to either of two over center positions, a drive shaft journaled to rotate independently of said operating shaft about its axis of rotation, said drive shaft having a laterally extending arm spaced from its axis of rotation and overlying said toggle carrier to engage one or the other of I said arcuately spaced shoulders thereon depending upon the direction of rotation of said drivesha-ft, and means for rotating said drive shaft to operate said toggle carrier from one over center position toward the other past the center position and operate said switch blade into and out of its closed position.

2. A mechanism for moving a switch blade into and out of bridging position with a pair of spaced switch contacts comprising, in combination, an operating shaft journaled to rotate about its longitudinal axis and operatively connected to said switch blade to move the same, a shaft cam secured to and rotatable with said operating shaft and having a pair of radially extending arcuately spaced shoulders, a toggle carrier journaled to rotate independently of said operating shaft about its axis of rotation and having a pair of radially extending arcuately spaced shoulders, a drive pin extending laterally from said toggle carrier and spaced from its axis of rotation and overlying said shaft cam to engage one or the other of said 'arcuately spaced shoulders thereon depending upon the direction of movement of said drive pin, a toggle link pivotally connected at one end by said drive pin to said toggle carrier and pivotally connected to a spring carrier at the other end, an elongated cylindrical spning guide stationarily mounted in spaced relation to said operating shaft with its longitudinal axis at right angles to said axis of rotation of said operating shaft for slidably receiving said spring carrier at one end, a coil compression spring interposed under substantial pretension between the other end of said spring guide and said spring carrier and biasing said toggle carrier to either of two over center positions, a stop at said one end of said spring guide limiting the outward movement of said spring carrier under the influence of said coil compression spring, a drive shaft iournaled to rotate independently of said operating shaft about axis of'rotation, said drive shaft having a laterally extending arm spaced from its axis of rotation and overlying said toggle carrier 'to engage one or the other of said arcuately spaced shoulders thereon depending upon the direction of rotation of said drive shaft, and means for rotating said drive shaft to operate said toggle carrier from one over center position toward the other past the center position to operate said switch blade into and out of its closed position.

3. A mechanism for moving a switch blade into and out of bridging position with a pair of spaced switch contacts comprising, in combination, an operating shaft journaled to rotate about its longitudinal axis and operatively connected to said switch blade to move the same, a shaft cam secured to and rotatable with said operating shaft and having a pair of radially extending arcuately spaced shoulders, a toggle carrier journaled to rotate independently of said operating shaft about its axis of rotation, a drive pin extending laterally from said toggle carrier and spaced from its axis of rotation and overlying said shaft cam to engage one or the other of said arcuately spaced shoulders thereon depending upon the direction of movement of said drive pin, means on said shaft cam limiting the movement of said drive pin away from one of said shoulders toward the other shoulder when said shaft cam occupies a predetermined position, a toggle link pivotally connected at one end by said drive pin to said toggle carrier and pivotally connected to a spring carrier at the other end, and elongated cylindrical spring guide stationarily mounted in spaced relation to said operating shaft with its longitudinal axis at right angles to said axis of rotation of said operating shaft for slidably receiving said spring carrier at one end, a coil compression spring interposed under substantial prctension between the other end of said spring guide and said spring carrier and biasing said toggle carrier to either of two over center positions, a stop at said one end of said spring guide limiting the outward movement of sad spring carrier under the influence of said coil compression spring, a drive shaft journaled to rotate independently of said operating shaft about its axis oflrotation, said toggle carrier having a pair of radially extending arcuately spaced shoulders, said drive shaft having a laterally extending arm spaced from its axis of rotation and overlying said toggle carrier to engage one or the other of said arcuately spaced shoulders thereon depending upon the direction of rotation of said drive shaft, and means for rotating said drive shaft to operate said toggle car "er from one over center position toward the other past the center position to operate said switch blade into and out of its closed position.

4. A mechanism for moving a switch blade into and out of bridging position with a pair of spaced switch contacts comprising, in combination, an operating shaft journaled to rotate about its longitudinal axis and operatively connected to said switch blade to move the same, a shaft cam secured to and rotatable with said operating shaft and having a pair of radially extending arcuately spaced shoulders, a cam pawl mt-atably mounted intermediate its ends on said shaft cam with a shoulder at one end facing one of said spaced shoulders on said shaft cam, a spring biasing said cam pawl to position said shoulder thereon, genenally in registry with said one shoulder on said shaft cam, means cooperating with said cam pawl when said shaft is rotated to a position corersponding to the bridging position of said switch blade to rotate said cam pawl and move said shoulder thereon out of registry with said one shoulder on said shaft earn, a toggle carrier journaled to rotate independently of said operating shaft about its axis of rotation, a drive pin extending laterally from said toggle carrier and spaced from its axis of rotation and overlying said shaft cam to engage one or the other of said arcuately spaced shoulders thereon depending upon the direction of movement of said drive pin and to engage said shoulder on said cam pawl when the same is in registry with said one shoulder on said shaft cam, a toggle link pivotally connected at one end to said toggle carrier and pivotally connected to a spring carrier at the other end, a spring guide stationarily mounted in spaced relation to said operating shaft for slidably receiving said spring carrier at one end, a coil compression spring interposed between the other end of said spring guide and said spring carrier and biasing said toggle carrier to either of two over center positions, a drive shaft journaled to rotate independently of said operating shaft about its axis of rotation, said toggle carrier having a pair of radially extending arcuately spaced shoulders, said drive shaft having a laterally extending arm spaced from its axis of rotation and overlying said toggle carrier to engage one or the other of said arcuately spaced shoulders thereon depending upon the direction of rotation of said drive shaft, and means for rotating said drive shaft to operate said toggle carrier from one over center position toward the other past the center position to operate said switch blade into and out of its closed position.

5. A mechanism for moving a switch blade into and out of bridging position with a pair of spaced switch contacts comprising, in combination, an operating shaft jou-rnaled to rotate about its longitudinal axis and operatively connected to said switch blade to move the same, a shaft cam secured to and rotatable with said operating shaft and having a pair of radially extending arcuately spaced shoulders, a cam pawl rotatably mounted intermediate its ends on said shaft earn with a shoulder at one end facing one of said spaced shoulders on said shaft cam and a cam surface on a tail portion at the other end facing toward said axis of rotation of said operating shaft, a spring reacting between said shaft cam and said cam pawl and biasing it to position said shoulder thereon generally in registry with said one shoulder on said shaft cam, a detent stationarily mounted adjacent said operating shaft and engageable with said cam surface when said shaft is rotated to a position corresponding to the bridging position of said switch blade to rotate said cam pawl and move said shoulder thereon out of registry with said one shoulder on said shaft cam, a toggle carrier journaled to rotate independently of said operating shaft about its axis of rotation, a drive pin extending laterally from toggle carrier and spaced from its axis of rotation and overlying said shaft cam to engage one or the other of said arcuately spaced shoulders thereon depending upon the direction of movement of said drive pin and to engage said shoulder on said cam pawl when the same is in registry with said one shoulder on said shaft cam, a toggle link pivotally connected at one end by said drive pin to said toggle carrier and pivotally connected to a spring carrier at the other end, an elongated cylindrical spring guide stationa rily mounted in spaced relation to said operating shaft with its longitudinal axis at right angles to said axis of rotation of said operating shaft for slidably receiving said spring carrier at one end, a coil compression spring interposed under substantial pretension between the other end of said spring guide and said spring carrier and biasing said toggle carrier to either of two over center positions, a stop at said one end of said spring guide limiting the outward movement of said spring carrier under the influence of said coil compression spring, a drive shaft jour-naled to rotate independently of said operating shaft about its axis of rotation, said toggle carrier having a pair of radially extending arcuately spaced shoulders, said drive shaft having a laterally extending arm spaced from its axis of rotation and overlying said toggle carrier to engage one or the other of said arcuately spaced shoulders thereon depending upon the direction of rotation of said drive shaft, and means for rotating said drive shaft to operate said toggle carrier from one over center position toward the other past the center position to operate said switch blade into and out of its closed position.

6. Means for opening and closing a high voltage current carrying circuit comprising, in combination, a pair of switch contacts in insulated spaced relation, a switch blade for bridging said switch contacts and movable into and out of engagement with one of said switch contacts, a load current interrupter including separable interrupter contacts and interrupter contact operating means for opening and closing said interrupter contacts, one of said interrupter contacts being connected to said one switch contact and the other interrupter contact being connected to said switch blade during that portion of its movement into and out of engagement with and adjacent to said one switch contact, means on said switch blade cooperat ing with said interrupter contact operating means during movement of said switch blade to open position to open said interrupter contacts after said switch blade disengages said one switch contact, means on said switch blade cooperating with said interrupter contact operating means while said switch blade is moving to closed position to close said interrupter contacts; and quick operating mechanism mechanically connected to said switch blade for moving it between closed and open positions including an over center spring operated toggle mechanism operable from one side of center where said switch blade is closed to the other side where said switch blade is open, operating means cooperating with said toggle mechanism in the switch closed position to move said toggle mechanism to the center position and stress the spring without moving said switch blade away from closed position until after said spring has been partly stressed and thereafter moving said switch blade out of engagement with said one switch contact and completing stressing of said spring, lost motion connecting means between said operating means and said switch blade whereby said spring after operation of said toggle mechanism past the center position accelerates said switch blade toward open position and separates said contacts of said load current interrupter at high speed to interrupt current flow; and means providing a direct driving connection between-said operating means, said toggle mechanism, and said switch blade when the latter is in the open position whereby said switch blade is moved toward the closed position and said Spring is stressed by movement of said operating means in a closing direction until said center position is passed whereupon said spring accelerates said switch blade toward closed position and closes said contacts of said load current interrupter.

7. Means for opening and closing a high voltage current carrying circuit comprising, in combination, a pair of switch contacts in insulated spaced relation, a switch blade for bringing said switch contacts and movable into and out of engagement with one of said switch contacts, a load current interrupter including separable interrupter contacts and interrupter contact operating means for opening and closing said interrupter contacts, one of said interrupter contacts being connected to said one switch contact and the other interrupter'contact being connected to said switch blade during that portion of its movement into and out of engagement with and adjacent to said one switch contact, means on said switch blade cooperating with said interrupter contact operating means during movement of said switch blade to open position to open said interrupter contacts after said switch blade disengages said one switch contact, means on said switch blade cooperating with said interrupter contact operating means while said switch blade is moved to closed position to close said interrupter contacts; and quick operating mechanism mechanically connected to said switch blade for moving it between closed and open positions including an over center spring operated toggle mechanism operable from one side of center where said switch blade is closed to the other side where said switch blade is open, operating means cooperating with said toggle mechanism in the switch closed position to move said toggle mechanism to the center position and stress the spring without moving said switch blade away from closed position until after said spring has been partly stressed and thereafter moving said switch blade out of engagement with said one switch contact and completing stressing of said spring, lost motion connecting means between said operating means and said switch blade whereby said spring after operation of said toggle mechanism past the center position accelerates said switch blade toward open position and separates said contacts of'said load current interrupter at high speed to interrupt current flow, stop means on said lost motion connecting means providing a direct connection between said switch blade and said spring for imparting to the latter kinetic energy in the former incident to its movement to the open position; means providing a direct driving connection. between said operating means, said toggle mechanism, and said switch blade when the latter is in the open position whereby said switch blade is moved toward the closed position and said spring is stressed by movement of said operating means in a closing direction until said center position is passed whereupon said spring accelerates said switch blade toward closed position and closes said contacts of said load current interrupter.

8. The invention as set 'forth in claim 7 wherein the spring in the toggle mechanism is a prestressed spring.

9. Means for openingand closing a high voltage current carrying circuit comprising, in combination, a pair of switch contacts in insulated spaced relation, a switch blade for bridging said switch contacts and movable into and out of engagement with one of said switch contacts,

a load current interrupter including separable interrupter contacts and interrupter contact operating means for opening and closing said interrupter contacts, one of said interrupter contacts being connected to said one switch contact and the other interrupter contact being connected to said switch blade during that portion of its movement into and out of engagement with and adjacent to said one switch contact, means on said switch blade cooperating with said interrupter contact operating means during movement of said switch blade to open position to open said interrupter contacts after said switch blade disene gages said one switch contact, means on said Switchblade cooperating with said interrupter contact operating meanswhile said switch blade is moving to closed position to initiate the closing movement of said interrupter contacts only after a circuit is completed between said blade and said one switch contact thereby avoiding cornpletion of the circuit in the first instance through said interrupter. contacts; and quick operating mechanism mechanically connected to said switch blade for moving it between closed and open positions including an over center spring operated toggle mechanism operable from one side of center where said switch blade is closed to the other side where said switch blade is open, operating means cooperating with said toggle mechanism in the switch. closed position to move said toggle mechanism to the center position and stress the springwithout moving said switch blade, away from closed position until after said spring has been partly stressed and thereafter moving said switch blade out of engagement with said one switch contact and completing stressing of said spring, lost motion connecting means between said operating means and said switch blade whereby said spring after operation of said toggle mechanism past the center position accelerates said switch blade toward open position and separates said contacts of said load current interrupter at high speed to interrupt current flow; and means providing a direct driving connection between said operating means, said toggle mechanism, and said switch blade when the latter is in the open position whereby said switch blade is moved toward the closed position and said spring is stressed by movement of said operating means in a closing direction until said center position is passed whereupon said spring accelerates said switch blade to complete the circuit between it and said switch contact at high speed followed by closure of said contacts of said load current interrupter and movement of said switch blade to fully closed position.

10. Means for opening and closing a high voltage current carrying circuit comprising, in combination, a pair of switch contacts in insulated spaced relation, a switch blade for bridging said switch contacts and movable into and out of engagement with one of said switch contacts, a load current interrupter including separable interrupter contacts and interrupter contact operating means for opening and closing said interrupter contacts, one of said interrupter contacts being connected to said one switch contact and the other interrupter contact being connectedto said switch blade during that portion of its movement into and out of engagement with and adjacent to said one switch contact, means on said switch blade cooperating with said interrupter contact operating means during movement of said switch blade to open position to open said interrupter contacts after said switch blade disengages said one switch contact, means on said switch blade cooperating with said interrupter contact operating means while said switch blade is moving to closed position to initiate the closing movement of said interrupter contacts only after a circuit is completed between said blade and said one switch contact thereby avoiding completion of the circuit in the first instance through said interrupter contacts; and quick operating mechanism mechanically connected to said switch blade for moving it between closed and open positions including an over center spring operated toggle mechanism operable from one side of center where said switch blade is closed to the other side Where said switch blade is open, operating means cooperating with said toggle mechanism in the switch closed position to move said toggle mechanism to the center position and stress the spring without moving said switch blade away from closed position until after said spring has been partly stressed and thereafter moving said switch blade out of engagement with said one switch contact and completing stressing of said spring, lost motion connecting means between said operating means and said switch blade whereby said spring after operation of said toggle mechanism past the center position accelerates said switch blade toward open position and separates said contacts of said load cur-rent interrupter at high speed to interrupt current flow, stop means on said lost motion connecting means providinga direct connection between said switch blade and said spring for imparting to the latter kinetic energy in the former incident to its movement to the open position; means providing a direct driving connection between said operating means, said toggle mechanism, and said switch blade when the latter is in the open position whereby said switch blade is moved toward the closed position and said spring is stressed by movement of said operating means in a closing direction until said center position is passed whereupon said spring accelerates said switch blade to complete the circuit between it and said switch contact at high speed followed by closure of said contacts of said' 

